Custom Add to Cart not functioning (Venture Theme)

Technical Q&A
1

I have created a custom add to cart on my shopping cart page.
the form is hard coded from the source code of the products page I wish to add to add to the cart.

the product adds to the cart fine, however when I change the variant, the same default variant is added to the cart each time. Am I missing some script/code needed for this to function correctly?

Many thanks in advance.

2

I have managed to get this working now.
I was missing some a script below the form and a div above which both seem to be required for the correct functioning.

If anyone wants to know what I did let me know and I’ll be happy to share.